Translation guide
The stoat is a small carnivorous mammal native to Eurasia and North America. In Japanese, it is most commonly referred to as オコジョ, but regional and literary terms exist.
Refer to the stoat as an animal in everyday conversation or writing.
The most common and widely understood term for stoat in modern Japanese. Used in zoos, nature documentaries, and general conversation.
北海道でオコジョを見ました。
I saw a stoat in Hokkaido.
Literally 'white weasel'. A less common term, sometimes used in literature or older texts. May be confused with other white weasels.
白鼬は冬に毛色が白くなる。
The stoat's fur turns white in winter.
Specifically refer to the stoat when it has its white winter fur, often associated with fur coats or heraldry.
Borrowed from English 'ermine'. Used for the white winter coat of the stoat, especially in the context of fur or fashion.
そのコートはアーミンの毛皮でできている。
That coat is made of ermine fur.
Literally 'white marten'. An uncommon term that may refer to the ermine, but is not widely used.
Unless you are specifically talking about fur or heraldry, オコジョ is the best word to use for stoat in Japanese. It is widely recognized and used in media.
The king's mantle was trimmed with ermine fur.